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  • A Real-World Example of a Stream Collector

    You can solve most use cases with one of the out-of-the-box collectors provided in the Collectors class.

    However, some require to implement a custom Collector, e.g., when you need to collect more than a single collection or a single scalar.

    While it may seem complicated if you never developed one before, it’s not. You only need a bit of practice.

    I hope this article might help you with it!

    Read more
  • Preventing YAML Parsing Vulnerabilities in Java

    YAML is a human-readable language to serialize data that’s commonly used for config files. The word YAML is an acronym for “YAML ain’t a markup language” and was first released in 2001. You can compare YAML to JSON or XML as all of them are text-based structured formats.

    YAML files are often used to configure applications, application servers, or clusters. It is a very common format in Spring Boot applications and, of course, to configure Kubernetes. However, similarly to JSON and XML, you can use YAML to serialize and deserialize data.

    Read more
  • Payara Services Wins Prestigious Queen’s Award!

    Micro-multinational open source software company, Payara Services, has been commended for its achievements within global trading and exporting with the Queen’s Award for Enterprise for International Trade.

    Now in its 55th year, the Queen’s Award for Enterprise: International Trade is the UK’s most prestigious business award, honouring organisations that have excelled in overseas exports whilst maintaining the highest standards in social, economic, and environmental activity.

    Jadon Ortlepp
    Read more
  • Elastic JVM: Configuring G1 GC for Automatic Vertical Memory Scaling

    Nowadays, JVM-based applications can benefit from elasticity and density of container technology. However, there are still some issues that prevent unleashing the full potential of Java and containers “marriage.”

    Releasing unused but committed Heap memory by the major JVM implementations based on OpenJDK, in most cases, is not performed automatically, or requires specific knowledge to be configured.

    Tetiana Fydorenchyk
    Read more
  • Why Java Developers Continue to Rely on Jakarta EE

    Over the past year, the Eclipse Foundation spoke to leading Java developers around the world to discuss why they rely on Jakarta EE and the unique benefits of using Jakarta EE technologies.

    Their input is captured in our white paper, which describes the important advantages Jakarta EE offers today and for the future.

    Ivar Grimstad
    Read more
  • Creating a Snake Game with JavaFX FXGL in Three Pair-Programming Sessions

    In this article, Almas and Frank show you how to start with an idea for a game and bring it to life in a prototype application. We will then modify the application to run on a Raspberry Pi and on a mobile device.

    To give some background, some time ago my 10y old son challenged me to create a Snake-like game with emojis. He selected the emoji images and I “only” needed to do the programming bit, the easy part… Luckily Almas asked me if I had a topic for some pair-programming for his YouTube channel, and his question turned into a three-part series. My son is delighted because his idea is now a real game!

    Almas Baimagambetov
    Read more
  • New Book: “Java Challengers”

    To get the best jobs and create massive value, you need to know Java very well. The newly released “Java Challengers” book is a way for you to challenge yourself with fun code challenges so that you will become a better Java developer.

    This book contains more than 70 well-elaborated Java Challenges that will help you break your limits on your Java skills. Want to challenge yourself and become better? The Java Challenges is the book for you!

    For each Java Challenge you get a full explanation to fully prepare you to beat the Java Challenge!

    To tease you with the Java Challenges book, try out the following challenges and see if you can solve them…

    Read more
  • A Close Look at Kotlin’s Delegation

    Kotlin offers many exciting features.

    In general, developers tend to cite null safety as their favorite. For me, it’s function extensions. But delegation comes a close second.

    The delegate pattern is ubiquitous in the Object-Oriented Programming world. Some languages, such as Kotlin, provides a native implementation.

    But delegation doesn’t stop at the class level. Kotlin does provide delegation at the property level. It provides some out-of-the-box delegates, but you can easily create your own.

    Read more
  • New to Java? Some Resources

    I was asked if I had a list of resources for developers who are new to Java. I didn’t at the time, but I’ve spent some time researching and here is that list.

    I’ve listed content that is both free and paid. It’s not that one type is superior; it’s just to give you plenty of choices. These are the resources that I’ve used and do still use to re-learn Java. So, if you’re new to Java or looking to pick it up again after a break, this article is for you.

    The other super important point is that everyone learns differently; some like reading, some like doing, some like watching, most of us like a bit of a mix of everything. I tend to switch between them depending on what I want to learn about and how I feel. You’re probably similar, so pick an approach that works for you.

    Read more
  • Fix Java Security Issues While Coding in IntelliJ IDEA

    Nowadays, developers are responsible for more than just creating the application. Besides working on features, developers have to focus on their applications’ maintainability, scalability, reliability, and security. Many developers are unsure of where to start with security. In addition, most companies still work with a dedicated security team instead of having security expertise inside the team.

    A lot of developers practically live in their integrated development environment (IDE). A good IDE is like a swiss army knife: it is your go-to tool to do almost everything. Having everything I need to build, run, test, debug, and secure my application, makes a good IDE invaluable for many developers.

    Read more

Best Java 16 Feature?

Oops. Error.

Java Version Almanac

Events Calendar

    • Virtual

    GeeCON 2021

    GeeCON is a conference focused on Java and Java Virtual Machine based technologies, with special attention to dynamic languages like Groovy and Scala. GeeCON is a forum for sharing experiences about modern software development methodologies, enterprise architectures, software craftsmanship, design …

    Event Page
    • Virtual

    QCon Plus

    A learning experience for senior software engineers. QCon Plus is an online experience where you can build your own learning journey. Learn from technical talks, engage in real-time live sessions, and develop new skills to validate your software roadmap.

    Event Page
    • Virtual

    Java Day Istanbul

    Java Day Istanbul is one of the most effective international community driven software conference of Turkey supported by Istanbul Java User Group. The conference helps developers to learn the newest technologies about Java, Web, Mobile, Big DATA, Cloud, DevOps, Agile …

    Event Page
  • GOTO Copenhagen

    GOTO is the enterprise software development conference designed for team leads, architects, and project management and is organized for developers, by developers. As software developers and architects ourselves, we wanted to craft the ultimate conference. The result is a high …

    Event Page
  • Voxxed Days Zurich

    Voxxed Days Zürich 2020 was cancelled due to the Coronavirus but we are already planning the next edition as soon as it will be possible. Current target date is June 15th, 2021. We will monitor how the situation evolves and …

    Event Page
  • GOTO Amsterdam

    GOTO is the enterprise software development conference designed for team leads, architects, and project management and is organized for developers, by developers. As software developers and architects ourselves, we wanted to craft the ultimate conference. The result is a high …

    Event Page
    • Virtual


    DevSecCon24 is a global, vendor-neutral, community-driven conference that connects developers, security and operations teams to learn and enable the integration of security into their development practices.

    Event Page
  • JavaZone

    JavaZone – the biggest European community-driven conference for modern developers will be 20 years old in 2021! Don’t miss out on two days of inspiring tech talks, a day of hands-on sessions, mingling, and a great party! JavaZone is organized …

    Event Page
    • Virtual

    JAX London

    Bringing together cutting edge software engineers and enterprise-level professionals innovating in the fields of JAVA, microservices, continuous delivery and DevOps.

    Event Page
  • Devoxx UK

    Devoxx UK is a 3-day conference where developers and architects come together and explore the latest technology advancements and fascinating ideas, with some of the most inspiring speakers in our sector. Diverse, local and global talent introduce the newest and …

    Event Page

OpenJDK Command Line Arguments

OpenJDK Terminology

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